1. Field of the Invention
The present invention relates generally to systems for observing and recording data relating to an article, and more particularly, but not necessarily by way of limitation, to a system for recording images, such as digital photographs, of at least a portion of an electrode utilized in an electric arc furnace, such as the stub end of the electrode, in order to record characteristics of the electrode.
2. Description of the Prior Art
One technique currently used for steel making is the use of an electric arc furnace that operates as a batch melting process producing batches of molten steel known as heats. The electric arc furnace operates on a cycle that includes the steps of furnace charging, melting, refining, de-slagging, tapping and furnace turn around. Modern electric arc furnace operations have a tap-to-tap time of approximately 60 minutes or less.
One of the most important elements in the electric circuit that provides the energy to melt the scrap steel in the electric arc furnace, is the electrode or electrodes. These electrodes deliver the electric power to the furnace in the form of an electric arc between the electrodes and the scrap steel and other materials making up the furnace charge that is to be melted. Electrodes come in two forms: amorphous and graphitic carbon, or graphite. Graphite electrodes are typically used in modern steel making.
The graphite electrodes are continuously consumed during the heating process in the electric arc furnace. Historically, electrode consumption has been as high as 12 to 14 pounds of graphite per ton of steel.
The electrodes are typically provided in cylindrical sections having threaded connections formed in each end thereof. The threaded sections are joined together to form a column of several electrode sections, which electrode column is adjustably placed within the furnace by a movable electrode holder arm that can raise and lower the electrode column, and can pivot to move the electrode column away from the furnace.
Electrodes are commonly available in sizes from 15 to 30 inches in diameter and in varying lengths up to about 10 feet.
In an AC electric arc furnace, there will be three electrode columns. In a DC electric arc furnace, there are one or two electrode columns.
During the steel making operation, the electrode column or columns are typically removed from the furnace at the end of each heat, and they may also be removed from the furnace during a heat in order to add additional charge materials to the furnace.
Historically, the performance of the electrode columns has been measured only in a gross fashion, such as cumulative monthly totals, so as to provide numbers such as the pounds of graphite required per ton of steel during the long term operation of the steel mill.
The physical condition of the electrode column has been visually observed during those instances when the electrode column is removed from the furnace, and from time to time anecdotal data may be observed and recorded in a manual fashion to describe the observed condition of the electrode column.
Furthermore, no attempt has been made to trace the identity of a given electrode section so that its observed performance can be correlated to various historical data such as operational parameters of the furnace, or manufacturing processes, raw materials employed, etc.
Accordingly, there is a need in the art for systems capable of viably monitoring and recording the condition or characteristics of the electrode column so as to permit subsequent analysis of and optimization of various operating parameters for the furnace and manufacturing processes associated with quality control.
The present invention provides methods and apparatus for recording information relating to the condition or characteristics of electrodes in an electric arc furnace. An imaging apparatus, such as a digital camera, capable of recording an image or other characteristics of the electrode is provided in a consistent position relative to an imaging station, such as a slip stand of the electric arc furnace. Periodically, when the electrode column is removed from the furnace, the stub end of the electrode column is placed upon the slip stand, and an image of the electrode column is made, such as with the digital camera. The images, such as digital photographs may then be stored for later analysis.
Preferably, the system also includes means by which the identity of a given electrode section, that comprises the electrode or portion thereof shown in a given image, can be identified and traced back through both its manufacturing process and its subsequent operational environment, so that the observed condition and/or characteristics of the electrode may then be correlated to one or more of those historical events to aid an improved quality control and optimization of both the electrode manufacturing process and the steel making process.
A unique system is provided for defining, and assigning numerical values to a plurality of recurring defective conditions or other characteristics. The numerical values are preferably assigned in a ranked numerical series that is constructed such that each possible sum value for the conditions present in a given electrode corresponds to a unique combination of defined conditions. The numerical series may be a binary series.
It is therefore an object of the present invention to provide improved methods and apparatus for observing and recording data corresponding to the condition or characteristics of an electrode column in an electric arc furnace.
Another object of the present invention is the provision of unique systems for defining and recording the observed conditions or characteristics utilizing numerical values representative of the observed conditions or characteristics.
Still another object of the present invention is the provision of systems that allow the subsequent analysis of recorded data for use in optimizing manufacturing processes, raw material selection and operational processes associated with the electrodes.
Other and further objects, features and advantages of the present invention will be readily apparent to those skilled in the art upon a reading of the following disclosure when taken in conjunction with the accompanying drawings.